Process for bonding and flame proofing webs of synthetic fibers

ABSTRACT

Method for forming a bonded and flame retardant non-woven web of synthetic fibers by treating a web of non-woven synthetic fibers with a thermosetting aminoplast resin, cyanamide and phosphoric acid, and thereafter heating said web at an elevated temperature.

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OBrien 1 1 June 11, 1974 SUBS'HTUTE FOR M1SS1NG X11 1 1 PROCESS FORBONDING AND FLAME 2.781.281 2/1957 Berger 117/136 O G WE 0 SYNTHETICFIBERS 2,953,480 9/1960 Burncll 1 17/137 3.047.425 7/1962 Hirshfield etal.. 117/136 X [75] Inventor: Samuel James 0 Bnen, Dunnellen, 3.253.8815/1966 Donahue 117/137 x NJ. 3.479.211 11/1969 Goldstein 117/136Assigneez American Cyanamid p y, 3.496.155 2/1970 0 Connor et al. 8/192Stamford, Conn. j 22 Filed: Nov. 13 1970 3 Primary ExaminerGe0rge F.Lesmes Assistant Examiner-J. Cannon PP' N05 8953] Attorney, Agent, orFirm-Charles Joseph Fickey [52] US. Cl. 156/331, 1013/15 FP, 117/136,117/137. 117/138.8 F, 117/138.8 N, [57] ABSTRACT 1 117/138.8 UA,161/403, 260/294, 2 60/DIG. I 24 Method for forming a bonded and Ham!retardant f C0915/06, 344d 1/ 844d 1/09 non-woven web of syntheticfibers by treating a web of Field of Search 156/331; 106/15 FF;non-woven synthetic fibers with a thermosetting ami- 252/81; 117/136,137 noplast resin, cyanagnide and phosghoric acid, and

thereafter heating said web at an elevated tempera- [5 6] ReferencesCited ture.

UNITED STATES PATENTS 2,488.034 1 1/1949 Pingree et al 1 17/136 6Claims, No Drawings PROCESS FOR BONDING AND FLAME PROOFING WEBS OFSYNTHETIC FIBERS The invention relates to a method for forming a bondedand flame retardant nonwoven web of syn-' thetic fibers.

Nonwoven webs of synthetic fibers, particularly poly- I ester fiberssuch as Dacron, are used as interliners in quilted outer garments. Suchwebs are made, as well known in the art, by random orientation ofsynthetic fibers in layers in any desired quantity, depending on thedensity and thickness desired in the final treated web. In view of thecurrent interest, especially the em phasis by the various governmentalbodies, in flame re- I such as polyester, polyamide and acrylic fibersmay be employed.

The thermosetting aminoplast resins of use in this invention are of theconventional types, and include melgninerforrnaldeliyde condensates,ureai'ormaldehyde condensates, uron-formaldehyde condensates,triazone-formaldehyde condensates, etc. The

thickness of 0.25 inch and heated at 160C. for five minutes. Theresulting bonded polyester web had a thickness of 0.25 inch and itsflame retardancy was commercially acceptable.

EXAMPLE 2 g A loose web of acrylic fiber was treated in a pad bathcontaining percent of partially methylolated trimethylolmelamine, 8percent cyanamide and 2 percent of 85 percent orthophosphoric acid, toobtain a wet pickup of about 250 percent. The treated web was dried forabout five minutes at 100C. and then clamped to a methylolated productscan'be alkylated by reaction with lower alcohols, also according toconventional procedures. The preferred resins are methylolatedpolymethylol melamines.

The resin, cyanamide and phgsphoricacidpan be applied simultaneously orseparately to the web. Solutions of the agents in water or other inertsolvent are conveniently applied by padding, spraying or dipping.

The amount of aminoplast resin applied to the web should be between 5percent and 25 percent, preferably between 7.0 percent and 15.0 percent,based on the weight of the web.

The amount of cyanamide applied to the web should be between 2 percentand 20 percent, preferably between 5 percent and 10 percent, based onthe weight of the web.

The amount of phosphoric acid applied to the web should be between 1percent and 5 percent, preferably between 2 percent and 3 percent, basedon the weight of the web.

The treated webs are dried to remove the water or other solvent and arethen heated at a temperature between l and 180C, preferably between 149and l63C.. to effect a cure of the aminoplast resin. l-fdesired, thethickness of the web can be maintained me chanically during the curingstep.

EXAMPLE l A pad bath containing 7.2 percent of a partially methmgedltimcfllflgL lsi-lamine, 5 percent of anamije and 3.3 percent of 85percent orthophosphoric acid was applied to a loose web of polyester(Dacron brand) fibers by a standard padding procedure. A wet pickup of300 percent based on the weight of the web was obtained. The treatedloose web was dried for five minutes at 105C, and the web was thenclamped to a thickness, of 0.25 inch and heated at 150C. for fiveminutes. The resulting acrylic web had a final thickness of about 0.25inch and commercially acceptable flame retardancy.

EXAMPLE 3 A polyamide web (Nylon) was treated as in Example 1, withsimilar results.

EXAMPLE 4 When the procedure of Example 1 was repeated with substitutionof an equal amount of dimethylol 4,5- dihydroxydiethyleneurea for thepartially methylolated trimethylol melamine, essentially the sameresults were obtained.

EXAMPLE 5 When the procedure of Example 1 was repeated with substitutionof an equal amount of dimethylolmelamine for the partially methylolatedtrimethylolmelamine, essentially the same results were obtained.

substitution of an equal amount of dimethylolurea for the partiallymethylolated trimethylol melamine, the

resulting polyester web had a high degree of flame retardancy. f lclairn:

1. A method for forming a bonded and flame retardant nonwoven web ofsynthetic fibers comprising impregnating the web with an aqueoussolution of a thermosetting aminoplast r sin, cyanamide and phosphoricacid and heating the web to effect a cure of the finish on the web.

2. A method as in claim 1 where the synthetic fiber is a polyester fiberand the thermosetting aminoplast resin is a melamine-formaldehydecondensation product.

3. A method as in claim 1 wherein the amount of aminoplast resin is fromabout 5 to 25 percent based on the weight of the web.

4. A method as in claim 1 wherein the amount of cyanamide is from about2 to 20 percent based on the weight of the web.

5. 'A method as in claim 1 wherein the amount of phosphoric acid is fromabout 1 to 5 percent based on the weight of the web.

6. A method for forming a bonded and flame retardant nonwoven web ofsynthetic fibers comprising impregnating the web with an aqueoussolution of a thermosetting aminoplast resin, cyanamide and phosphoricacid and heating the web to effect a cure of the finish on the web, saidheating being at a temperature of about 130 to lC.

2. A method as in claim 1 where the synthetic fiber is a polyester fiberand the thermosetting aminoplast resin is a melamine-formaldehydecondensation product.
 3. A method as in claim 1 wherein the amount ofaminoplast resin is from about 5 to 25 percent based on the weight ofthe web.
 4. A method as in claim 1 wherein the amount of cyanamide isfrom about 2 to 20 percent based on the weight of the web.
 5. A methodas in claim 1 wherein the amount of phosphoric acid is from about 1 to 5percent based on the weight of the web.
 6. A method for forming a bondedand flame retardant nonwoven web of synthetic fibers comprisingimpregnating the web with an aqueous solution of a thermosettingaminoplast resin, cyanamide and phosphoric acid and heating the web toeffect a cure of the finish on the web, said heating being at atemperature of about 130* to 180*C.